Tag: fireball

[Update to the update (Oct 25): Apparently, the rock found is not actually a meteorite. These things can be tricky to identify, and the first conclusion was mistaken. Bummer.]

[Update to the update to the update; that is, update 3: (Oct 26): OK, see if you can follow along, since I barely can. A rock was found that was thought to be a meteorite from the fireball, and then thought not to be. Well, guess what? It’s back on the list! A second rock was found a few kilometers away and identified as a meteorite, which prompted Peter Jenniskens to look over the first one again. He has concluded it actually is a meteorite. At this point, I think I’ll hold off re-dis-un-updating all this, and if there’s more news, I’ll start a new blog post. Thanks to BABloggee Mike McJimsey for the link.]

They’re reporting Peter Jenniskens, a SETI astronomer and meteorite expert, confirmed the find. That’s critical: a lot of rocks are mistaken for meteorites by people (and the media) who aren’t familiar with them. This chunk is small, though, and given how bright the fireball was and how it was seen to fragment, I’d think bigger pieces must have fallen. That area is fairly well-populated – I used to live not far from there and cursed traffic every time I had to endure it – so hopefully more pieces will turn up.

The beauty of this is that because it was seen by several cameras and dozens of witnesses, the path across the sky can be well-determined. That can be backtracked in space to see where in the solar system it came from. And with an actual piece of that asteroid in hand, we can learn more about what conditions are like in parts of space we would otherwise have to send probes to explore.

It’s planetary science, and we get it essentially for free! And we got a really cool light show to go along with it. Everyone wins.

A lot of folks are speculating that this is part of the Orionid shower, which peaks this weekend. The direction and timing for the meteor are wrong for that though, so it’s certainly not an Orionid. Meteor showers generally don’t make fireball like this. Also, showers are pretty frequent, so any random bright meteor has a decent chance of occurring during one just by coincidence. So be wary of claims like that.

The noise reports appear to be real, though. Some people say their houses were shaken like in an earthquake. This means the meteoroid (the solid part ramming through our atmosphere) was of a decent size (like a beachball, maybe? Hard to say) and got low enough in the atmosphere to have the sonic boom carried by air. Most small meteoroids burn up 100 km or so above the Earth, so no noise is heard. The noise coupled with the obvious fragmentation mean that there may be meteorites that hit the ground from this event. It’s not yet clear if it fell over the ocean or not, so I’ll try to keep up with the news and update this post as I find out more.

If you live in the US and ever do see a fireball, it’s a good idea to note the direction it’s traveling and your location as best you can, and then report it to the American Meteor Society. If you get pictures or videos, send them to me! I’d love to post them if I can.

Marco Langbroek is a paleolithic archaeologist in Amsterdam, and also an amateur satellite tracker – though with modern tech, the term "amateur" is arguable. Anyway, he’s been looking at the track and velocity of the meteor using eyewitness accounts (and the video taken), and thinks he can rule out the cause being the re-entry of human-made debris from a spacecraft. In fact, he thinks the meteoroid (the term for the actual object responsible for the light show) was an Aten asteroid: part of a class of rocks that orbit the Sun on paths that tend to keep them inside Earth’s orbit*.

The key issues here are the slow speed it moved across the sky, and the fact it moved east-to-west. That last part is really important: very few satellites orbit retrograde, or in that direction. Most orbit either prograde – west-to-east, the same direction the Earth spins and also the same direction it orbits the Sun – or in polar orbits (north/south). So right away that makes it unlikely the meteor was from a spacecraft.

However, what has me scratching my head is the slow speed of the meteor. A rock orbiting the Sun retrograde means its velocity will add to the Earth’s, making it move faster as it burns up, not slower. It’s like two cars in a head-on collision; if each is moving 100 km/hr then the resulting collision speed is 200 km/hr relative to either car. You get slower relative collisions if they’re moving in the same direction; they’ll merely bump at low speed relative to one another.

We see this with meteors; the Leonid meteor shower, for example, is made up of tiny particles that move almost in the opposite direction of the Earth, and when they burn up in our atmosphere they move extremely rapidly across the sky. The collision speeds can be 70 kilometers per second!

So why was this meteor over the UK moving so slowly if it were an Aten? Marco thinks he has the answer to that. If the asteroid happened to be at aphelion – the top of its orbit, when it’s farthest from the Sun, also when moving most slowly and in a direction nearly parallel with that of the Earth – it would all add up. The backwards direction and the slow motion would be a natural consequence of this. [UPDATE: I made an error here: the asteroid can orbit the Sun prograde! When it’s at the top of its orbit, it can be moving slower than Earth does around the Sun, so when we look at it it appears to move east-to-west. It’s like passing a slower car in a faster one; to the driver of the passing car, the slower one appears to be moving backwards when in reality they are both moving in the same direction. I hope that clears up any misunderstanding!]

I’ll note that as far as I have thought about this, I agree with Marco. It’s not conclusive yet, though, but it’s compelling.

Meteors like this are rare. One that gets this bright, is seen by so many people, and drops bits of itself as it burns up are rare enough (the Peekskill meteor in 1992 is the best example of this), but one moving retrograde is even weirder. If Marco is right then I hope even more people submit their observations, pictures, and videos to the International Meteor Organization website. Those observations can help scientists determine the orbit of the object more accurately, and help pin down exactly what the heck this crazy object was.

* Technically, an Aten asteroid has a semi-major axis less than one Astronomical Unit. Orbits are elliptical, and the semi-major axis is the half-diameter of the orbit along the long axis. Despite this, an Aten can cross the Earth’s orbit if its orbit is elongated (eccentric) enough.

Twitter just exploded with reports, pictures, and videos of an extremely bright fireball moving over the northern part of the UK at around 22:00 UTC. I’ve seen tweets from folks in Ireland, Manchester, and more. It was traveling east-to-west, and broke up into many pieces as it fell. No reports of it hitting the ground yet, though some pieces may fall all the way down.

Here’s the best video I’ve seen so far:

Other videos are not as clear but do show the same object (note the positions of the individual pieces as they move). Here’s one from Ross Shankland:

It’s too early to tell, but this may be a actual meteor – that is, a rock burning up – or it may be space debris, a piece of a satellite re-entering. Meteors tend to move quickly, zipping across the sky in a few seconds; they are moving at 20 – 50 kilometers per second and sometimes more. Orbital debris is slower, moving at less than 10 km/sec. Both have been known to break up (like the Peekskill meteor did, or the re-entry of an ATV in 2011).

I’ll update this as I get more info. But I have to say how jealous I am of everyone who saw this! And if you did witness it, you should file a report with the IMO, so they can collect all the info – it may help lead to finding meteorites, pieces that have made it all the way down to the ground!

On April 22, 2012, a chunk of asteroid one or two meters across burned up in Earth’s atmosphere. It came in over California and was seen by a lot of people, despite it occurring at about 8:00 a.m. local time and in broad daylight.

I just became aware that some footage was taken of the event, and as far as I know is the only video we have of it. It was taken by Shon Bollock, who was making a time-lapse kayaking video just outside Kernville, California as part of his Shasta Boyz adventuring website:

The video is being studied by astronomers and meteoriticists to try to calculate the trajectory, speed, and possible orbit of the object. This is difficult with just one video, so if you have pictures you took or, better yet, more video, please let me know!

Photographer Tony Rowell sent me a link to a time lapse video he made of the American southwest. It’s all really very pretty, but honestly, the part that got me was the amazing lenticular cloud at the very beginning. You just have to see it to believe it!

Spectacular, no? Lenticular, or lens-shaped, clouds form near mountains, where the rising air condenses to form the clouds, and the wind gives them their shape. I see them commonly here in Boulder, but near sunset the colors are magnificent. Tony really snagged a great shot there, and I love how it looks like a jellyfish hovering in the air.

Finally, right at the end (at the 4 minute mark) he caught a bright fireball over Mt. Whitney that’s just stunning.

It appears over several frames of the time lapse, which isn’t actually possible: meteors move so quickly they come and go in a single frame exposure (or at most just a few, depending on the exposure times)! I asked Tony about it, and he acknowledged that the meteor was slowed down after the fact in the video so you get a better view of it. I expect some people might think this is cheating, but I wouldn’t agree. After all, a time lapse itself might be considered cheating! It’s an artistic representation of reality, and I think it’s OK to let the art triumph, as long as it’s clear that’s the case.

Reports are coming in of a very bright fireball over Germany, Belgium, and the Netherlands. It happened around 16:30 GMT (17:30 local time in that part of Europe) on December 24 (just a couple of hours ago as I write this). I heard of it when BA Bloggee Dave Grant sent me a note from Dusseldorf; he got video of it!

If you are in that area and saw it, you can report it to the International Meteor Organization or to The Latest Worldwide Meteor / Fireball Reports (note: I found that last site doing a bit of searching and I’m not familiar with it, so I don’t know how official it may or may not be. There are links in the sidebar there to other organizations). make sure you list your position as best you can, and what direction you were looking.

If you did see it, and have pictures or video, please leave a comment below with a link! It’s a holiday, but I can try to post some of the better shots/footage. The more actual footage there is, the better astronomers can trace both the direction from which it came, and the location of any possible meteorites.

[Update: It looks like the cause of this was a gas bottle exploding, and not a meteorite. See the update for 21:15 UT below).]

A deadly explosion and fire occurred in Argentina overnight, reportedly killing one woman and injuring several others. Two homes, a store, and several vehicles were destroyed or damaged.

The thing is, while it’s not clear what caused this incident, several people said they saw a ball of fire descend from the sky when it happened.

Neighbors’ accounts describe a ball of fire coming from the sky as the cause of the explosion. The chief of the firefighters, Guillermo Pérez, however, said the "causes remain unknown" and that "gas containers were found intact," ruling out a gas related incident.

Other reports are similar; in that article the ball of fire was described as being blue. I know a lot of folks will think this was caused by a meteor, but it’s a bit early to run with that yet. For one thing, it could’ve been a small plane on fire, for example; this happened very early in the morning (2:00 a.m.), and from the reports I’m seeing it’s not clear if the witnesses were already awake when they saw this or were awakened by it. Eye witness reports are notoriously unreliable, and it can’t help if the witnesses were suddenly woken up.

[Update (17:30 UT): This is looking less like a meteorite to me; this news story has a witness saying he saw the blue fire after hearing the explosion, and after he went outside to see what was what. Thanks to JoseManuelp2 for the link.]

As testament to that, I’m seeing some reports that the ball was red, and a picture was posted to the imaging site yfrog claiming, without any any supporting evidence, to be a shot of it. I include it here; note it’s very dark, out of focus, and very low resolution (from the pixelation). I have no clue what this picture shows, but I have my doubts it’s a fireball. I expect we’ll be seeing lots of rumors and things like this today.

[Update (21:15 UT): The image shown here of the red fireball is a hoax, and the man responsible for it has been arrested. Also reported in that link is that there were gas bottles secretly hooked up to a pizza making stove in a nearby house, and that this may be the cause of the explosion. I expect that is the final straw on this story — enough evidence is piling up that this was not something form space, or even from the sky; it was some kind of terrestrial event, as expected.]

The explosions and devastation appear to be very real, though. This is the only video I could find on YouTube, and it has no audio, but it shows the aftermath:

I don’t see any obvious airplane wreckage, but it’s hard for me to see that a meteorite impact would’ve done this; for it to have been big enough to cause this much devastation, there would’ve been a big crater as well (like the one that hit in Peru a couple of years back). None is evident, so I’m strongly of the opinion something more terrestrial was to blame here.

I won’t be surprised to hear people asking if this was from the UARS satellite, too. However, that’s pretty much impossible; the satellite came down Friday night, and there couldn’t have been pieces of it still in orbit two days later. Also, again, the type of destruction seen here is unlikely to have been from just a simple impact.

Hopefully we’ll find out soon. If you hear anything please leave a comment below (with a link if you have one), and I’ll post an update when I learn more.

That was a fireball — an extremely bright meteor — that blew in over Atlanta, Georgia on August 28. The video is from the webcam at the Tellus Museum of Science in Georgia, part of the All Sky Fireball Network (I wrote about them recently when this same camera caught the space station passing overhead, in fact). The other streak you can see moving is an internal reflection in the camera, I believe, which shows you just how bright this fireball was.

Since there are four cameras in the network, they could triangulate on the meteor, getting its height off the ground. Coupled with its apparent speed, that tells them it was screaming in at more than 83,000 kph (52,000 mph)! Given how bright it was, I suspect it was probably about the size of a grapefruit or so. Funny how something that small can make such a bright streak, but then speed is the key here. The brightness of a meteor depends on how much energy it can deposit in the atmosphere, and that is determined largely by its kinetic energy. That, in turn, depends on its mass and its velocity… and these things are moving far, far faster than a rifle bullet.

The Tellus webcam caught other meteors that night too, which you can see here. They’re getting lots of information about the debris that hits us. And since about 100 tons of material enters Earth’s atmosphere every day, there are plenty of interesting things to discover!

A few days ago, the web was abuzz with something that looked like a very large meteor burning up over Peru. Here’s video from ITN news:

You can find similar videos on Youtube. However, is it actually a meteor?

Cutting to the chase, I don’t think so. I don’t have a lot of solid evidence either way, but all signs point that way. Here are my thoughts:

1) Meteors tend to move more quickly. They usually burn up around 100 km (60 miles) up, roughly, and are moving at a minimum of 11 km/sec (7 miles/sec) — Earth’s gravity pulls them in to at least this speed. If you’ve ever seen a meteor you know they zip across the sky in at most a few seconds.

2) The two trains (the technical term for what most people would call the tail or trail) are very odd — you can see them in the frame grab here. I’ve never seen a meteoroid (the actual solid bit moving through our atmosphere) produce more than one train. I don’t think this is an optical effect due to the camera but actually two distinct trains.